Avery Shipping Address Labels, Laser & Inkjet Printers, 20 Labels, Half Sheet Labels, Permanent Adhesive, TrueBlock (18126) Permanent adhesive is guaranteed to stick and stay put on cardboard, envelopes, paper, glass or metal. No more jams or smudges with Avery shipping labels. White labels optimized for laser & inkjet printers. TrueBlock technology covers up everything underneath the shipping label so you can reuse boxes. Easily customize these printable labels with thousands of free templates and designs at avery.com/templates. Great for bulk shipping and mailing, organizing boxes, bin labels, classroom organization & stickers, filing & organizing, and wine labels.